The problem of relapse continues to plague public health efforts to reduce the prevalence of cigarette smoking. Recent evidence suggests that a large percentage of individuals attempting smoking cessation lapse to smoking within a matter of days, and that very few of these individuals are able to recover to achieve abstinence from smoking. Current models of relapse devote insufficient attention to this phenomenon of early lapse. Given the physiological and psychological disruption that occurs within hours of nicotine deprivation, nicotine withdrawal might be expected to play a strong role in early lapse and subsequent relapse, yet results of studies attempting to relate severity of nicotine withdrawal symptoms to short-term smoking cessation outcomes have been equivocal. Recent findings suggest the need for an expanded perspective recognizing the central role of negative affect in nicotine withdrawal. In this regard, we believe that the study of factors surrounding sensitivity to symptoms of nicotine withdrawal is a promising avenue of investigation. The overall aim of this B-Start application is to examine variables that index a latent sensitivity to the negative emotional distress that occurs in the context of a smoking cessation attempt, Specifically, the present proposal will examine the extent to which distress tolerance and anxiety sensitivity, variables theoretically linked to an underlying sensitivity to negative emotional distress, predict early lapse among regular smokers. It is hypothesized that anxiety sensitivity and tolerance for emotional distress on a laboratory stressor task will predict the duration of quit attempt even after controlling for baseline levels of negative emotionality and smoking characteristics. We expect that the results of this study will provide a more comprehensive understanding of variables that might serve as indicators of an inherent sensitivity to negative affect and thereby contribute to early relapse to smoking. Early relapsers represent a recalcitrant group of smokers who are at-risk for continued nicotine dependence and its associated morbidity and mortality. Findings from this investigation should result in improved methods of identifying smokers at-risk for early lapse, so that they may be targeted for nicotine dependence treatments that will meet their specific needs.